Problem: $ { \left[\begin{array}{rrr}{3} & {3} & {1} \\ {0} & {-2} & {0}\end{array}\right]+\left[\begin{array}{rrr}{0} & {2} & {0} \\ {1} & {-1} & {4}\end{array}\right] = {?} } $
Explanation: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rrr}{3}+{0} & {3}+{2} & {1}+{0} \\ {0}+{1} & {-2}+{-1} & {0}+{4}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{3} & {5} & {1} \\ {1} & {-3} & {4}\end{array}\right]}$